December 29th, 2006 - by Sheeri Kritzer

Welcome to the 25th edition of Log Buffer, the DBA community?s Carnival of the Vanities-style blog of blogs about the database world.

This is the last Log Buffer of calendar year 2006. The database world seems to be a series of series lately, so let’s jump right in:

If, like me, you have no idea what doors and signals are in Solaris 10, you might want to read part 4 of Frank Mash’s “Managing MySQL on Solaris 10″, entitled Solaris Doors and Signals.

On a more theoretical level, Random Notes describes lack of …

From the blogosphere I get this feeling that everyone who writes up
a predictions post for 2007 believes that the iTV is going to be a
hit. Let me describe why it might just suck:

1) DRM. Front Row, the media interface for the Mac, was
useless for me until I found a plugin which would allow me to enable
all video formats. I pull video from the web from many sources. Front
Row was useless until I made it universal. If iTV doesn't allow
consumers to get past whatever DRM Apple has sold its soul for then
its going to be very niche. By niche I mean iTunes store only.

2) Speed. I have a lot of content available via Front Row. The
interface is just slow when it hits a directory with a lot of files
in it. When I push the button on the remote I expect an action to
occur. The current "pause" is just annoying, I think it will drive
…

As you might noticed there are no recent MySQL Community versions available for download from MySQL Download Area This applies both to binaries (which is expected with new polices) but also to the source files which were promised to be available.

So what is if you would like to use recent MySQL code while staying with community version ? I chatted with Monty on this topic today.

Download sources from MySQL FTP Site I have no idea why this location is not advertised on download pages but it really has sources for all recent releases, both for Unix and Windows.

Use MySQL Supplied by Distribution Vendor. Some vendors already offering MySQL 5.0.30 - Gentoo, Ubuntu and Debian at the time of this writing. Fedora might also get update soon.

…

Brian Aker recently wrote about a "skeleton project" for quickly bootstrapping a development environment for a new software project. I do something similar for Perl programs that I want to connect to MySQL.

So, if your a frequent reader of this blog you know that I've mentioned thatI federates data.

So, if all servers are the same, query load is the same, and the same amount of data exists on all the shards then the overall load average and IO load metrics should be the same between each server containing it's slice of the data (these are called shards).

Well, looking over some very detailed stats, I noticed that these new boxes that are in production are kicking some major ass, these new boxes are able to handle nearly 5 times more data and queries. To good to believe, since overall they are the same as my old boxes but the main difference is the CPU in them.

Then I looked at some more my.cnf.tmpl tweaks (I have a my.cnf.tmpl that generates my.cnf by replacing certain fields when /etc/init.d/mysqld start is invoked). Low and behold I added innodb_file_per_table and innodb_open_files=1024. This must be the …

As preparation for the upcoming Quality Contribution Program, a new MySQL forum was created today.
The new forum is dedicated to Quality Assurance matters. It is not the place where to submit bugs (there is already the bug reporting system for that purpose). It is rather a place where to discuss quality assurance problems, such as:

• How do I report this particular kind of bug?
• How do I make a test case for this specific situation?
• What is the best strategy to report a nasty cluster of bugs?
• Improving testing techniques;

Everything related to Quality assurance can be discussed there. If you have an idea on how to make better test cases, go there and launch the challenge. If you want to experiment a new technique for bug hunting, let's hear it! …

In the last year, we've seen open source software explode into the telecommunications market.  Typically telco equipment manufacturers, carriers and the like are on the bleeding edge of technology adoption, so this is really no big surprise.  The only surprise is how fast they've migrated from home-grown and proprietary software to open source.  Some of the largest deals MySQL closed in the last year were in the telecommunications industry, who are heavy users of MySQL Enterprise and MySQL Cluster.  This includes such well known companies as Alcatel, Cisco, Deutsche Telekom, Ericsson, France Telecom, Motorola, Nokia, Nortel, Telio, Vodafone and many others.

We've also started to see a new generation of "Web meets Telco" companies, like Tellme Networks, build almost completely on open source.  …

MySQL has two ways to find tune execution of particular query. First is MySQL Hints, such as SQL_BIG_RESULT, STRAIGHT_JOIN, FORCE INDEX etc. You place these directly into the query to change how query is executed for example
SELECT STRAIGHT_JOIN * FROM A FORCE INDEX(A) JOIN B

The other part is session variable. If you know query is going to require large sort you can do SET sort_buffer_size=50000000 before executing query and SET sort_buffer_size=DEFAULT after executing the query.

I noticed in production hints are used much more frequently than setting session variables for given query execution even though it also can be quite helpful and I believe the problem is it is more complicated. It also requires more round trips to the server but it is not that critical as it is complicated queries which normally need special values.

Especially if you're patching third party application it is much …

Casting can be evil... Assuming that bool will be one byte is a sin. Inside the source we do have my_bool which will be one byte but people forget that they are not the same type!

People will ask this question again and again when they run at the solidDB Storage Engine. The difference means, of course, the difference against InnoDB--the seminal transactional storage for MySQL. It is natural one would think, at first, that solidDB is just a clone of InnoDB because it does the same job of maintaining a transactional table engine under a unified SQL interface. That is true--and must be true--to some extent. However, when you scratch the surface, you may find some pleasant surprises. For example, built-in in solidDB is online backup producing snapshot-consistent backups in a non-blocking fashion. You may find a snapshot-consistent checkpoint a nice feature too. It gives you the freedom to move around the database files (after server shutdown) without the need to care about log files. There are also two concurrency control methods called "optimistic" and "pessimistic".

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